Fangrui Song 201572e34b [AArch64] Implement -fno-plt for SelectionDAG/GlobalISel ...

Clang sets the nonlazybind attribute for certain ObjC features. The
AArch64 SelectionDAG implementation for non-intrinsic calls
(46e36f0953) is behind a cl option.

GCC implements -fno-plt for a few ELF targets. In Clang, -fno-plt also
sets the nonlazybind attribute. For SelectionDAG, make the cl option not
affect ELF so that non-intrinsic calls to a dso_preemptable function use
GOT. Adjust AArch64TargetLowering::LowerCall to handle intrinsic calls.

For FastISel, change `fastLowerCall` to bail out when a call is due to
-fno-plt.

For GlobalISel, handle non-intrinsic calls in CallLowering::lowerCall
and intrinsic calls in AArch64CallLowering::lowerCall (where the
target-independent CallLowering::lowerCall is not called).
The GlobalISel test in `call-rv-marker.ll` is therefore updated.

Note: the current -fno-plt -fpic implementation does not use GOT for a
preemptable function.

Link: #78275

Pull Request: https://github.com/llvm/llvm-project/pull/78890

2024-03-05 13:55:29 -08:00

55 KiB

Raw Blame History

View Raw